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Publication
Featured researches published by You-Shin Shim.
Journal of Chromatographic Science | 2013
Jaeho Ha; You-Shin Shim; Dongwon Seo; Ki-Jin Kim; Masahito Ito; Hiroaki Nakagawa
A reverse-phase ultra-high-performance liquid chromatography (u-HPLC) method was developed for the rapid quantification of 22 ginsenosides in ginseng products. The proposed method for the analysis of ginsenosides is based on a heating-block method without further treatment. The u-HPLC separation was performed on a reversed C18 column (100 × 2 mm id, particle size 2 µm) followed by ultraviolet detection at 203 nm. Aqueous 50% methanol was used as the extraction solvent. The optimum amount of extraction solvent and the optimum extraction time were 20 mL and 20 min (extracted twice with 10 mL), respectively. The method validation parameters yielded good results for linearity, precision, accuracy and recovery. The recovery of ginsenosides from ginseng powder was greater than 98.1% and the limits of detection and quantification of the u-HPLC analysis were >0.6 and >1.8 mg/kg for ginsenosides. The calibration graphs for ginsenosides were linear from approximately 2.6 to 40.4 mg/kg for u-HPLC. The inter-day and intra-day precisions (relative standard deviation values) were <14.6 and 14.7%, except for Rg2(R) + Rh1(R).
분석과학 = Analytical science & technology | 2014
Jaeho Ha; You-Shin Shim; Yongsun Cho; Dongwon Seo; Hyewon Jang
The aim of this study was to establish an analytical method for the determination of E,E-farnesol and squalene in makgeolli, which is a traditional type of Korean fermented rice wine. E,E-farnesol and squalene in makgeolli were extracted using stir bar sorptive extraction (SBSE) coupled with gas chromatography-mass spectrometry. SBSE was found to be an effective method for analyzing the E,E-farnesol and squalene levels in makgeolli. The linear dynamic range of the SBSE method for detecting E,E-farnesol and squalene ranged from 0.5 to 200 ng/mL with R 2 =0.9974 for E,E-farnesol and 100 to 50000 ng/mL with R 2 =0.9982 for squalene. The limit of detection and the limit of quantification using the SBSE method were 0.1 and 0.5 ng/mL for E,Efarnesol and 15.0 and 40.0 ng/mL for squalene, respectively. The average recoveries obtained were, quantitatively, 101-107% for E,E-farnesol and 98-103% for squalene, respectively, supporting the accuracy of the SBSE-GCMS method.
Korean Journal of Food Science and Technology | 2013
Eunsil Lee; You-Shin Shim; Dongwon Seo; Jinbong Hwang; Songjin Lee; Jaeho Ha
Bamboo Resource Research InstituteAbstract We assessed the quality of a bamboo shoot vinegar produced in Damyang-gun in terms of parameters thatincluded acidity, mineral contents, amino acids, and flavonol aglycones. The flavor compounds of the bamboo shootvinegar were also analyzed using the stir bar sorptive extraction (SBSE) method. The acidity of the bamboo shoot vinegarwas 4.49%, which was the lowest value among the commercial vinegars studied. The bamboo shoot vinegar had a lowerconcentration of Na (8.36 mg/100 g) than the other commercial vinegars. There was a relatively large amount of tyrosineand lysine in the bamboo shoot vinegar. The concentration of quercetin, a flavonol aglycone, was 3.29 mg/100 g. Theresults of the flavor analysis showed that hexanal, 2-furancarboxaldehyde, and benzaldehyde were high in the bambooshoot vinegar. Oleamide, a compound that is known to induce sleep, was first found in bamboo shoot vinegar using theSBSE method.Keywords: bamboo shoot, vinegar, flavor, stir bar sorptive extraction, oleamide
Analytical Sciences | 2011
Jaeho Ha; Dong-Won Seo; Xi Chen; Jinbong Hwang; You-Shin Shim
Food Science and Biotechnology | 2010
Jaeho Ha; Hye-Young Seo; You-Shin Shim; Dongwon Seo; Ho-Moon Seog; Masahito Ito; Hiroaki Nakagawa
Journal of AOAC International | 2013
You-Shin Shim; Ki-Jin Kim; Dongwon Seo; Masahito Ito; Hiroaki Nakagawa; Shohei Arai; Jaeho Ha
한국식품영양과학회 산업심포지움발표집 | 2015
Yun-Yeol Lee; You-Shin Shim; Haebin Cho; Byung-Joo Kim; Joonhee Lee; Sang-Do Ha; Jinbong Hwang
한국분석과학회 학술대회 | 2015
So-Young Kim; Mi-Ra Oh; Hyunjun Lee; You-Shin Shim; Byung-joo Kim; Junhee Lee; Mi-Ok Yang; Jinbong Hwang
한국분석과학회 학술대회 | 2015
Mi-Ra Oh; So-Young Kim; H.-S. Lee; You-Shin Shim; Dongwon Seo; Youngmin Chol; Se-Na Kim; Jin-Sik Nam; Mi-Ok Yang; Jinbong Hwang
한국분석과학회 학술대회 | 2014
Dongwon Seo; Yongsun Cho; Haewon Jang; You-Shin Shim; Jaeho Ha